Machine for sharpening rock-drills.



B. H. LOGKE. MACHINE FOR SHARPENING ROCK DRILLS.

APPLICATION FILED JUNE 4,19 0'7.

Patented Sept. 15, 1908.

2 SHEETS-SHEET 2..

IM My UNITED STATES RATENT BEIGE.

BRADFORD H. LOOKE, OF NEW YORK, N. Y.

MACHINE FOR SHARPENING ROOK-DRILLS.

T 0 all whom it may concern:

Be it known that I, BRADFORD H. LOOKE, a citizen of the United States,residing in the borough of Manhattan, of the city of New York, in theState of New York, have invented certain new and useful Improvements inMachines for Sharpening Rock-Drills, of which the following is aspecification, reference being had to the accompanying drawings, forminga part hereof.

Rock drills or drill bits, especially those used with power machines,commonly have their cutting edges in the form of a cross. They areusually sharpened or reset by hand r with the aid of suitable appliancesand by reason of the shape of the cutting ends, above referred to, muchskill is required in sharpening or resetting them. Moreover, muchdifficulty is involved in the sharpening of such drills when, as isgenerally the case, they have long stocks and are of considerable size.

It has been proposed, heretofore, to provide machines for the pupose ofsharpening such drills, but such machines have not come into generaluse, partly, perhaps, for the reason that the drill itself has been heldstationary and the sharpening die has been made to strike the end of thedrill. Much floor space is required for machines of this characterbecause the meohanism which reciprocates the die or hammer must be inline with the drill itself. Moreover it is impossible to make use of theweight of the die or hammer and its carrier in striking the blow becauseit is generally impracticable to support the drill vertically frombelow. It has also been pro posed to reciprocate the drill itselfhorizontally, causing it to strike a stationary die, but in such amachine the advantage of the weight of the reciprocating part instriking the blow is lost, and moreover the shaping of the drill headcan not be properly effected with a die against the face of which thedrill head is made to strike. It is the object of the present inventionto overcome the difliculties above alluded to and to produce a drillsharpening machine which shall be cap able of giving to the drill headthe exact shape desired and in which the full weight of the drill itselfshall be taken advantage of in striking the forming blow, while themachine itself occupies but little floor space and can be readilyoperated.

In accordance with the invention the drill is made to reciprocatevertically with the die secured to its head or working end, the latterSpecification of Letters Patent.

Application filed June 4, 1907.

I striking upon a suitable anvil at each reciprooation so that the drillis driven by its own momentum into the die and is made thereby to takethe desired shape.

hereinafter with reference to the accompanying drawings in which it isillustrated as embodied in a suitable mechanism.

In the drawings-Figure l is a view in side elevation of a drillsharpening machine which embodies the invention, the anvil support beingshown partly in section. Fig. 2 is a view of the same in frontelevation. Fig. 3 is a detail view in section on the plane indicated bythe line 3 3 of Fig. 1, looking downward, on a larger scale. Fig. 4 is adetail view in section on the plane indicated by the line 44 of Fig. 1,also looking downward, 1

In the machine shown in the drawings the working parts are supportedupon a substantial frame a. In suitable bearings at the top of the frameis mounted a shaft 6 which may be driven by any suitable means, as by abelt 0 from a motor (Z. A head 6, suitably guided in the front frame afor vertical movement, is reoiprocated through the usual spring andstrap connection f of a power hammer from a crank pin 1) carried by acrank disk D on the shaft 1). The head e is adapted to have the drillstock g firmly se cured thereto that it may reciprocate therewithvertically. For this purpose a suitable clamp h is provided, the samecomprising, as shown in the drawings, links it which are pivoted uponthe ends of studs 7L carried by the head e, and a front cross bar orclamping bar 71,3 which is pivotally connected to the links it at oneend and at the other end is engaged by eccentric clamping devices hfwhich are carried by the links it at that side.

A wedge 72,, with its thick end down, is preferably interposed betweenthe cross bar 7L3 and the shank of the drill stock 9 so that the anvilbelow it, through the interposed die, shall be to cause the drill to bemore securely held. Below the drill and in line therewith is placed asuitable anvil t, having a plain striking face.

The die 7r which is to shape the drill head is so formed as to becapable of being secured to the working end of the drill stock and toreciprocate therewith, striking upon the anvil 'i at each reciprocation.The construction of the die 76 may vary according to The invention willbe more fully explained eifect of the blows of the drill against the.

the work to be done. The die shown in the drawings comprises a headblock 7c adapted to strike upon the anvil t and having its working facesuitably formed to give the desired shape to the drill face, and twomembers k and k which are adapted to embrace the drill head and to givethe desired shape thereto. The two members k and k are pivotally mountedupon a stud 10 carried by the head block 7c and are provided each with atapering lip or projection is, or one with a straight lip and the otherwith a tapering lip, both of which are adapted to be embraced by a clampor yoke 7c which is pivotally mounted upon the head block 76 and isprovided with weighted arms k which serve to hold the clamp or yoke inplace when the machine is in operation. For convenience in constructionthe pivot block 7c of the yoke or clamp is and the stud k may be securedto the head block k by a single bolt 70 as shown in Fig. 1.

In the operation of the machine the drill to be sharpened is firmlyclamped to the reciprocating head 6 and the die is is clamped upon itsend the drill being so set in the clamp h as to permit the head block 7rto strike the anvil i. Power is then applied to the shaft 1) as by meansof the belt tightener Z and foot lever m, and the die is batteredagainst the anvil i. In this operation the drill head is graduallyniushroomed within the die until it takes the shape of the die chamberand is thereby sharpened or reset.

The operation of sharpening the drill is carried on quite rapidly forthe reason that the entire weight of the drill and of the reciprocatingparts which carry it is utilized in striking the anvil. Moreover, themachine requires for its operation but an extremely limited floor spaceand no pit, the drill being held vertically above the anvil. N oadjustment of the die or of the drill in its holder is required afterthe drill is once properly set, for-the reason that as the die travelswith the drill it is driven further upon the stock of the drill as thehead is formed and the yielding of the mechanism which reciprocates thedrill is sufficient to compensate for such shortening of the drill astakes place through the formation or sharpening of the head.

It will be obvious that various changes in details of construction andarrangement can be made to suit different conditions of use Withoutdeparting from the spirit of the in Vention.

I claim as my invention:

1. A die .for sharpening drills and adapted to be secured to the drillhead, the same comprising a head block, die members pivotally mountedthereon and adapted to embrace the drill head, and a clamping devicecarried by the head block and engaging the die members to hold themsecurely about the drill head.

2. A die for sharpening drills and adapted to be secured to the drillhead, the same comprising a head block, a stud carried thereby,

die members mounted upon said stud and having projecting lips and a yokepivoted upon the head block and engaging said proj ecting lips tohold'the die members securely about the drill head.

3. A die for sharpening drills and adapted to be secured to the drillhead, the same comprising a head block, a stud carried thereby, diemembers mounted uponsaid stud and having projecting lips and a yokepivoted upon the head block and engaging said projecting lips to holdthe die members securely about the drill, said yoke having a weightedarm to hold it in engagement with the lips of the die members.

This specification signed and witnessed this 31st day of May, A. D.1907.

BRADFORD H. LOOKE.

Signed in the presence of- ELLA J. KRUGER, AMBRosE L. OSHEA.

